Apple peel flour instead of sugar in sponge cake: Nutritional, sensory, physical, and microbiological evaluation

Apple peels are considered "inedible parts," however, they can be dehydrated and ground to use as an ingredient in bakery products. The present study aims to evaluate the replacement of 25% and 50% sugar in sponge cakes for apple peel flour (APF) cakes by comparing their nutritional composition, sugar profile, microbial development, sensory preference and acceptability, color, and specific volume. The results showed that by incorporating APF into sponge cakes, the dietary fiber content increases, and the concentration of total sugars and energy intake significantly decrease. As disadvantages, it is revealed that APF does not inhibit microbial development and the specific volume decreases when incorporating APF. The sample with the greatest preference and sensory acceptability corresponds to the 25% sugar replacement with APF.